Indium oxide ($\mathrm{I}{\mathrm{n}}_2{\mathrm{O}}_3$)

Indium oxide usually denotes indium(III) oxide, $\mathrm{I}{\mathrm{n}}_2{\mathrm{O}}_3$, a solid chemical compound of indium and oxygen. Formal oxidation states of $+3$ for indium and $-2$ for oxygen give charge balance: $2(3)+3(-2)=0$. The formula expresses the elemental ratio; it does not imply discrete molecules in the solid.^[ref]

Doping this oxide with tin produces the material family indium tin oxide, used for transparent conducting layers. Electrical and optical performance depend on charge-carrier density and preparation, so knowing the host compound's formula alone does not specify a film's conductivity.^[ref]